What is the difference between salt quenched martensite and oil quenched martensite?

Salt-quenched martensite and oil-quenched martensite, the structure is basically the same. The cooling rate of salt bath quenching in the high-temperature area is faster than that of oil, the structure is finer, and the possibility of drosnia is small. If the salt-quenched martensite is not cooled twice, the austenite content is generally higher than that of oil quenching, because the salt bath temperature is higher and generally 170-190.

Therefore, the salt quenching production line is equipped with a secondary cooling station, which can reduce the participating austenite to about 8% after secondary cooling.

The difference in cooling speed will definitely affect the quenching structure, even if the difference in hardness is not obvious, in the case of quenching, the workpiece with fast cold speed quenching is more needle-like m, and the slats with slow cooling speed m are more. View the original post

Salt water quenching and oil quenching are determined according to the material of the part, and not everything can be quenched. Sweeping Reed Feihong: What furnace are you introducing, the quenching temperature should be determined according to the material, and tempering is also a reason View the original post

In a sense: since they are all obtained martensitic tissue, there is no substantial difference. View the original post

I would like to take this opportunity to ask if the different cooling rates of the quenching medium can affect the tissue level of quenching (the same heating temperature time) View the original post

Reply 1 What is the best temperature for salt quenching martensite, and we also want to introduce a furnace that uses salt quenching, but I don't have any experience with these, please give me some advice, thank you! View the original post

Hardened steel, high carbon or other element alloy steel, the surface is quenched, the overall performance is hard, wear-resistant, commonly used in molds, washers, bearings, etc.;

The main purpose of heat treatment is to remove austenite and carbide, further enhance and optimize the metallographic structure to achieve the effect you want, martensitic hardness refers to the hardness of this structure; Could it be that you are asking about the name of hardness? Brinell, Rockwell, Pasteur? Rockwell hardness is commonly used.

Strength, usually refers to several aspects, according to the different ways of external force, mainly yield strength, tensile strength, compressive strength, bending strength, etc., engineering commonly used is yield strength and tensile strength, these two strength indicators can be measured by tensile test.

The name quenching is a non-professional name, I don't know if you refer to the depth of the hardened layer? Or does it refer to the quenching temperature.

It is recommended that you study this metal science.

Let's talk about soxlet and tempered soxenite first: these two are easy to distinguish, the essence is that soxlet is isotherm transformation from supercooled austenite, and the essence belongs to the alba-like pearlite.

It is generally called fine pearlite, and the droschild we are talking about is called very fine pearlite; Tempered sostenite is made from martensite.

It is transformed from high-hood temperature detection and tempering, and the essence belongs to granular pearlite, that is, the fine-grained cementite dispersed on the equiaxed ferrite matrix.

Then there is martensite and tempered martensite, which are not very different and can only be compared with these two organizational differences of the same part. Martensite is tempered at a low skin fiber temperature and then converted into tempered martensite, which is generally tool steel or bearing steel.

And the surface quenching steel adopts low temperature tempering, the hardness and strength are slightly reduced after tempering, the toughness is increased to a certain extent, and the structure is more stable.